Insulated collector



Patented Oct. l5, 1929 UNITED STATES PATENT OFFICE RALPH E. FERRIS, OF BWISSVALE, PENNSYLVANIA, ASSIGNOB TO WFSTINGHOUSE ELECTRIC MANUFACTURING COMPANY, A CORPORATION OF PENNSYLVANIA INSULATED Application llled lay 31,-

My invention relates to current-collecting devices for dynamo-electric machines.

Heretofore, in making collector rings, it has been customary to provide either a base of insulating material in which the collector rings were embedded or a plurality'of concentric sleeves of insulating material over which the collector rings were forced.

With the formen method, it has been found that the bod-y of the insulating material did not have sufficient mechanical strength to withstand the forces incident to o eration. With the latter method, considera le diiliculty has been encountered in assembling the concentric sleeves of insulating material, since it has been necessary to provide sleeves of very exact dimensions in order that they may fit tightly together.

Furthermore, when utilizing the concentric sleeves mentioned above, it was necessary to insert the connectors or terminals in the sleeves of insulating material before the collector rings were forced on. The connections between the terminals and the collector rings were made after the collector rings had been forced on, so that the electrical connection between the two members was often quite imperfect.

One of the objects of my invention is to provide a current-collecting device which is rigid in construction and relatively easy to assemble.

Another object of my invention is to' provide a current-collecting device in which the terminals and collector rings may be con-` nected before the device is assembled.

A further object of my invention is to provide a current-collecting device which will have a body of rigid material which may be forced on a machine shaft after the device is assembled.

In the accompanying drawing, Fig. 1 is a longitudinal sectional view of a current-collecting device embodying my invention,

Fig. 2 is a view, in end elevation, of the structure illustrated in Fig. l, and

Fig. 3 is a fragmentary view, showing a transverse section taken on the line III- III of Fig. l.

In the embodiment of my invention shown COLLECTOR 1927. serai no. masas.

in the accompany-ing drawing, a hollow cylindrical body member or bushing 1 of steel is Wrapped with a plurality of layers 2 and 3 of fiexible mica. Three collector rings, 4, 5 and 6, of good-conducting material, arranged to it the mica-wrapped bushing 1, are shrunk thereon and spaced at equal longitudinal intervals.

The left-hand collector ring 4 has an obiong slot or groove 7 extending longitudinally across its under side. One end 8 of a flat terminal 9 of good-conducting material is disposed in the slot 7 and secured to the collector ring 4 by any suitable means, such as welding or soldering. The terminal 9 is encased in a iiat tubular member 11 of insulating material and is disposed longitudinally along the smooth outer periphery of the wrapped bushing 1.

The middle collector ring 5 is similar to the one described above, except that it has two slots or notches 12 and 13 spaced 120o apart around its inner periphery; Oneof the slots 12 is similar to the single slot 7 of the 'left-hand collector ring and serves to connect with a terminal strip 14. The other slot 13 is somewhat larger and is arranged to admit the insulated portion 11 of the fiat Vterminal 9, which is attached to the left-hand collector ring 4.

A third collector ring 6, similar to the second ring 5, and having, in addition, a second large slot 15, is disposed at the right-hand end of the bushing. The three slots in this collector ring are disposed at equal distances around the inner periphery of the ring.

A third fiat terminal 16, similar to those described above, is secured in the small slot in this collector rin The right-hand collector ring 6 is dispose upon the bushing 1 in such position that the fiat terminals connected to the middle ring and the left-hand ring will eX- tend through the two larger slots.

A quantity of as haltic cement 17 is disposed around the tu lllar members 1l enclosing the terminals, thereby providing additional (protection against grease and dirt and, in ad ition, providing a relativel smooth surface which may be easily wipe( clean of dirt and grease or any other material lending to and easy to assemble.

provide a short-circuit path between adj acent collector rings.

In assembling my device, the terminals are each joined to their respective collector rings.

The tubular insulating members, which have been shaped to fit over the terminals, are then slipped over the latter. Finally the collector rings are heated and forced on the bushing which has previously been wrapped with sheets of flexible mica.l When the rings cool, they contract and are held securely in position and also maintain the terminals in their proper positions.

By my invention, ll provide a current-collecting device which is simple 'and rugged In addition, am able to connect the terminals 'and rings before the device is assembled.

I claim as my invention:

i. A collector-ring assembly comprising a cylindrical metallic supporting member, a substantially smooth insulating material therearound, and a plurality of slip rings disposed, in spaced relation, on said insulating' material intight, frictional engagement9 therewith, each of said slip rings having a dat terminal member secured thereto, said terminal members being enclosed in individual tubular insulating members and extending longitudinally alongside the fiat outer surface of said layer of insulating material, some of said slip rings being rooved in their under surfaces toreceive the tu ularinsulating member of-a terminal oflanother slip ring, the junction between each ring and its terminal member being of a` type requiring no more space, inthe radial direction, than the thickness of said terminal member with its tubular insulating enclosure in place.

2.- A collector-ring ,assembly comprising a cylindrical metallic supporting member, a substantiall smooth insulating material therearoun and a plurality of slip rings disposed, in spaced relation, on said layer of insulating material in tight, frictional engagement therewith, each of said slip rings having a iat terminal member secured thereto, said terminal members being enclosed in individual tubular insulating members and extending longitudinally alongside the flat outer survface of said layer of insulating material, some of said slip rings being grooved in their under surfaces to receive the tubular insulating member of a terminal of another slip ring, and a body of insulating material disposed over said 'terminal members andv providing a smooth outer surface.

3. A collector-ring assembly comprising a cylindrical metallic supporting member, asubstantially smooth insulating material therearound, and a plurality of slip rings disposed, in spaced relation, on said insulating material in tight, rictional engagement therewith, each of'said slip rings having a dat-bottomed groove inthe inner periphery rings being grooved in their under surfaces to receive the tubular insulating member of a terminal of another slip ring, the junction be- -tween each ring and its terminal member requiring a radial depth at least as small as the depth of said last-mentioned grooves.

material in tight, rictional engagement therewith, each of said slip rings having a flat-bottomed groove in the inner periphery thereof and a fiat terminal member molecularly in-` tegrally `joined to said dat bottom of said groove, said terminal members being enclosed in individual tubular insulating members and extending longitudinally alongside the fiat outer surface of said layer of insulating material, some of said slip rings being groovedin their under surfaces to receive the tubular insulating member of a terminal of another slip ring, the junction between each ring and its terminal memberrequiring a radial depth at least as small as the depth of said last-nien! tioned grooves. v In testimony whereof, l have hereunto subscribed my name this 25th day of May, 1927.

RALPH E. FERRIS.

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